The Texas Tech University Health Sciences Center has a number of faculty who are currently engaged in research which requires the separation, detection and analysis of complex mixtures of proteins. Several of these investigators are using two- dimensional gel electrophoresis (2-D PAGE) followed by silver- staining, autoradiography or fluorography to accomplish this separation and detection. The major investigators listed in this proposal are using 2-D PAGE in an attempt to detect proteins which may by important in the regulation of steroidogenesis, the control of events involved in implantation, those which may serve in regulating the growth, development and metabolisms of skeletal muscle, proteins which may be synthesized as a result of estrogen action on the uterus, outer membrane proteins which are synthesized and secreted by various mutants of E. coli, and lastly, proteins which may be involved in the recognition of cells to be removed during tadpole tail regression. Examples of autoradiograms and fluorograms of 2-D gels generated in several of these studies appear in the text of this proposal. The methodology for the separation and detection of proteins mentioned above is currently being utilized, however, the analysis of 2-D gels other than visual is not yet possible due to a lack of the necessary equipment. Therefore, this proposal is requesting funds to purchase a computer assisted two- dimensional gel scanning device which is essential to the successful analysis of the protein patterns described herein. These scanning systems are available commercially and are able to perform both quantitative and qualitative analyses of proteins separated by 2-D PAGE. In addition to the scanning of 2-D gels, we anticipate that this instrumentation will also be used for the analysis of 1-D gels and dot-blots as well as for image analysis of cells, subcellular organelles and particles on photomicrographs which are being analysed by a less sophisticated and much slower "Bioquant" imaging system currently in use at TTUHSC.